Apparatus for gelling and vulcanizing rubber



9 sheetsneet 1 INVENTOR. ma; V9,

T. J. R. DlBDlN APPARATUS FOR GELLING AND VULCANIZING RUBBER Oct. 17,1950 Filed Feb. 14, 1948 Oct. 17, 1950 T. J. R. DlBDlN APPARATUS FORGELLING AND VULCANIZING RUBBER Sheeis-Sheet 2 Filed Feb. 14, 1948VZINVEN TOR.

Oct. 17, 1950 T. J. R. DIBDIN APPARATUS FOR GELLING AND VULCANIZINGRUBBER Filed Feb. 14, 1948 9 Sheets-Sheet 3 INVENTOR.

7! 49M "QM Oct. 17, 1950 T. J. R. DlBDl N APPARATUS FOR GELLING ANDVULCANIZING RUBBER 9 Sheets-Sheet 4 Filed Feb. 14, 194B Oct. 17, 1950 T.J. R. DlBDlN APPARATUS FOR GELLING AND VULCANIZING RUBBER Filed Feb. 14,1948 9 Sheet s-Sheet 5 IN V EN TOR. j

Oct. 17, 1950 T. J. R. DlBDlN APPARATUS FOR GELLING AND VULCANIZINGRUBBER Filed Feb. '14,. 1948 9 Sheets-Sheet 6 .Ild.

INVENTOR.

Oct. 17, 1950 J, DlBDlN r 2,526,461

APPARATUS FOR GELLING AND VULCANIZING RUBBER Filed Feb. 14, 1948 9Sheets-Sheet I INVENTOR.

* @ZW M 1950 T. J. R. DlBDlN 2,526,461

APPARATUS FOR GELLING AND VULCANIZING RUBBER Filed Feb. 14, 1948 9Sheets-Sheet 8 Oct. 17, 1950 T. J. R. DlBDIN 2,526,461

I APPARATUS FOR GELLING AND VULCANIZING RUBBER Filed Feb. 14, 1948 9Sheets-Sheet 9 adapted to form with means for transporting r PatentedOct. l7, 19 56 APPARATUS FOR GELLING AND VULCANIZIING RUBBER ThomasJames Rimbault Dibdin, Liverpool, Eng"- land, assignor to Dunlap Tireand Rubber Corporation, Bufialo, N. Y., a corporation of New YorkApplication February 14, 1948, Serial No. 8,373

In Great Britain February 11, 1947 Section 1, Public Law 690, August 8,1946 Patent expires February 11, 1967 6 Claims.

My invention relates to improvements in apparatus for gelling andvulcanizing rubber arti cles, particularly foamed compounded aqueousdispersions of rubber.

It is known to make sponge rubber articles by passing moulds containinga compounded aqueous dispersion of vulcanizable rubber in a foamedgelled condition through a tank of hot water, or by placing the mouldsin an atmosphere of steam within an autoclave, whereby vulcanization ofthe foamed dispersion is effected. It has been found, however, that themovement of the moulds containing gelled but unvulcanized foameddispersion necessitated by these prior methods tends to produceobjectionable ripple surfaces on the final product.

My present invention provides apparatus for gelling and vulcanizingrubber in the form of an aqueous dispersion whereby movement of themoulds containing the dispersion prior to and during the gelling andvulcanization operation is obviated.

In my invention, apparatus for gelling and vulcanizing rubber articlescomprises a base for supporting rubber articles at two stations in sidemovable cover-member by side relationship, a

the base at each station a chamber for enclosing an article at saidstation, the said cover member from the one station to the other, andmeans to admit steam within the cover member at each ofsaid stations.

Advantageously the said base is provided with means for preventing thedevelopment ofa pressure greater than atmospheric'within the chamber. I

The various features of the invention are illusvention and Fig. VIB is avertical section on the center lineof the right part of th apparatus.

Figs. VIIA and VIIB are plan views of the left and right parts of theapparatus shown in Fig. VI.

Fig. VIII is an end view of the apparatus shown in Fig. VI, the lefthalf being in section on the line A-A of Fig. VIA and Fig. IX .is a halfvertical section on the line B-B of Figure VIA.

Fig. X is a detail view illustrating a hydraulic cylinder and valveconnections of the apparatus of Figs. VIA-IX.

Referring first to Figures I to comprises essentially a base I formed ofgirder members and sheet metal and of suitable height for a workman tomanipulate moulds thereon, the top of the base being formed with twostations 2 and 3 for moulds extending lengthwise of the top of the basein side by side relationship. A cover 4 is provided adapted to be placedover either of .the stations 2 and 3; for this purpose the coverisjoined at one end to parallel arms V, the apparatus '5 and 6, the upperend of arm 5 being pivotally nected to shafts 9 and II) respectivelywhich are trated by way of example in the accompanying f drawings inwhich:

Fig. I represents a sectional elevation of an apparatus embodying theinvention taken on the line A-A of Figure IV.

Fig. II is an end elevation of shown in Figure I.

Fig. III is a plan view of the half of the ap-. paratus of Figure Iwhich is uncovered.

Fig. IV is a side view ofthe apparatus partly in elevation with thecover in a lowered position, and partly in section with the cover in araised position.

Fig. V is a detail illustrating the arrangement of pipe work forsupplyingwater to the spray pipes of the apparatus of Fig.1

- Fig. VIA is a side elevation of the left part of apparatus embodyinganother form of the inthe apparatus A mounted in bearings II and extendlengthwise of the apparatus one beneath each of the stations 2 and 3;the other ends of shafts 9 and H! are connected to arms which are inturn each pivotally connected to the cover in like manner to arms 5 and6. Beneath the base 2 adjacent toeach end of the shafts 9 and iii aretwo parallel arms l2 rigidlyconnected thereto, Figs. I and IV, the lowerends of these arms being pivotally connected toQa-link IS. The links G3at either end of the apparatus are connected by a trough member H5 inwhich weights can be placed to balance the cover 4. Cover 4 can thus bemoved from one station to the other by rotation of the shafts 9 and Illcausing the parallel arms 5 and 6 to is packed aluminium foil-ll forheat insulating purposes, the walls 15 and I6 being spaced apart byfourlengths of L-section girder l8. defining the rectangular mouth ofthe cover. Bonded to the girder is a-sealingstri-p 19 of rubber or otherresilient material extending around the entire perimeter of the mouth. Aspray pipe 20 to which water can be supplied by means to be describedsubsequently extends lengthwise centrally of the cover adjacent to thetop of the inner wall. Projecting laterally from each side of the coveradjacent to the mouth thereof are two pairs of slit lugs 2i and 22 (oneof each pair being visible in Figs. I and II) and the bench is providedwith two pairs of levers 24, 24a, pivotally mounted at 25, 25a andhaving pins 23, 23a adapted to engage with the lugs. One pair of leversis mounted at each side of the bench, one lever of each pair beingvisible. Near the center of the bench two levers 2B are providedeachrotatably mounted on vertical pins 21 projecting upward from the bench.With the cover in the position shown in Figure I pins 23 of levers 24engage lugs 2i of the cover while levers 26 engage lugs 22, and thusmaintain the seal between the cover and the bench. When the cover is inposition over station 3 it is similarly maintained in sealingrelationship with the bench by engagement of pins 23a of levers 2:20.with lugs 22, and engagement of levers 26 with lugs 2|.

Each station 2 and 3 of the mould is similarly constructed but ofopposite hand, and it will be sufiicient to describe the one on the lefthand side of Fig. I. The station is defined by a rectangular framework28 of T-shaped girder members, one flange of the T-projecting upwards tocontact the sealing strip ll of the cover, while a second flange of eachgirder projects inward and together the flanges form a ledge extendingthe whole way round the station. On the ledge is supported atrough-shaped bottom 29 sloping downwardly to an outlet 33 for liquid,beneath which outlet is an S-pipe 3| disposed in known manner to form atrap to prevent the escape of steam. A number of bars 32 resting ongirders 28 form supports for moulds placed thereon. If desired, thesebars may in turn support a platform of perforated sheet metal on whichmoulds can be supported which are too small to be supported on adjacentbars 32. Extending lengthwise and centrally of the trough immediatelybeneath the bars 32 is a perforated pipe 33 through which cooling watercan be sprayed onto moulds supported on the bars 32. This water can bedelivered through pipe 35 controlled by valve 36 (see Figure V), on theoutlet side of which is a branched pipe; one branch 38 passes throughthe bottom of trough 29 at 34 and delivers water to the spray pipe 33while the second branch 31 communicates through a non-return valve 39with one arm of a T-piece ill, a second arm of which T-piece isconnected by a flexible pipe 4| to the spray pipe 20 in the cover. Asimilar spray pipe 42 is disposed at the station 3 to which water can besupplied by pipe 43 controlled by a further valve (not shown) similar tovalve 35 of Figure V and from which pipe 43 a further pipe 31a branchesand communicates through a non-return valve 44 with the third arm ofT-piece 40. It is thus possible to spray water on to moulds at thestation 2 both from pipe 2!] and spray pipe 33 by opening valve 36, thewater passing along pipe 3? being prevented from passing into the pipe43 by virtue of non-return valve 44. When the cover is in position overstation 3 water can be sprayed over moulds at that station from thespray pipe 20 within the cover and the spray pipe 42 by supplying waterfrom.

4 the second valve (not shown) similar to valve 36; water then passingto the spray pipe 23 through lpipes 37a and 4| but not into the pipe 37because of the non-return valve 39.

At the side of the trough 29 adjacent to one edge of the apparatus aretwo steam inlets 45 to which steam can be supplied through valve 36 andpipework 41. The cover is also provided with a thermometer 48. In thefloor of each trough 29 is a flap valve or valves adapted to openinwardly.

The use of the above apparatus will now be described with reference tovulcanizing in closed moulds a foamed rubber latex compounded to gel inthe cold. It will be assumed that the cover is not in the position shownin the diagram but in its other position over station 3, and that anumber of moulds can be put on each station simultaneously. Mouldsfilled with the foamed ungelled dispersion are put on the bench atstation 2 and are allowed to stand until gelling has taken place. Bymanual operation the cover l is swung from the station 3 to cover themoulds at station 2, the sealing strip I9 being brought to rest on theT-piece 28; the cover 4 is clamped down in this position by means of thelevers 24, 26. The trough 29 co-operating with the cover thus forms anenclosed space around the moulds to which steam can be supplied asdesired to carry out the vulcanization operation. For this purpose valve46 is opened to permit steam to be delivered through inlets 35; some airwill then be displaced through the S-pipe 3i and condensation will occuron the inside of cover i and trough 9 and the outside of the mould. Thiscondensate will in part escape through pipe 3|, and the remainder willcollect in the bend thereof and form a seal. As the temperature withinthe apparatus approaches C., as shown by the thermometer E8, the supplyof steam is cut down so that this temperature is maintained withoutcondensate in the S-pipe 3! being blown out, and this condition ismaintained until vulcanization is complete. The supply of steam is thencut off and valve 36 is opened to deliver water to the spray pipe 20through pipes 31 and M and to spray pipe 33 through pipe 38. The waterdelivered on to the moulds in this manner will cool then and then escapethrough pipe 3|, and the water is then cut off at valve 36. Reduction inpressure within the apparatus caused by condensation of steam duringthis operation will be prevented by relief valves 50. Whilevulcanization is proceeding in this way at station 2, further moulds areplaced on the apparatus at station 3, filled with foamed dispersion, andleft to gel as above so that they will be ready for vulcanization whenthe treatment of the foam in the moulds within the cover has beencompleted. This vulcanization having been carried out, the cover 4 ismoved to its alternative position over station 3 thus uncovering themoulds containing the now vulcanized foam at station 2 and covering themoulds at station 3 containing the foam awaiting vulcanization.vulcanization is then carried out as has been described above, themoulds being finally cooled from the water supply fromjspray pipe 23 andspray pipe 42, the water for pipe 23 now being delivered through pipe 43and 41. While this is proceeding themoulds containing the vulcanizedproduct atstation 2 are removed, further moulds put in their place andfilled with foam in like manner.

tially of bars 64 over a sloping trough 58 be-.

neath the top of the bench 50, with a drain 59 at the lowest point ofeach trough covered by gauze 60. Articles on bars 64 can be sprayed withwater from a hose pipe (not shown) The two vulcanizing stations 53 and54 are similar in construction and it will be sufiicient' to de- 1scribe one of them. Each has a flat perimeter BI and a bottom formed ofa, trough 52 sloping down to an outlet 63, protected by gauze 55, .in

communication with a trap for condensate (not shown) similar tothatdescribed with reference to Figs. I to V. Adjacent to one edge ofthe -troiigh are two inlets 56 through which steam can be suppliedthrough a valved pipe (not shown).. Two water spray pipes 5! extendlengthways of the apparatus within the trough 62 by which cold water canbe supplied as de- Slightly below the sired through inlet pipe 58. flatperimeter 51 of each station are transverse supporting bars 59- on whichmoulds can be supported. The trough 52 has two flap valves 12 hinged attheir highest edge and adapted to open inwards.

The apparatus is also provided with a cover 19 which is movablelengthways of the apparatus on a carriage H. The cover is double walledand of sufficient depth to enclose moulds placed on the apparatus ateither vulcanizing station, and has a mouth of size and shape such thatit fits the fiat perimeter 5| of either vulcanizing station; a sealingstrip 12 ensures that a sound seal is obtained between the cover and theperimeter. The carriage H is formed of two side members 13 disposedparallel to the side members 52 of the base and joined by transversechannel shaped members 14 extending underneath the base 50; thesetransverse members 14 are provided with buffers 15 of rubber or otherresilient material which contact the respective legs 5| of the apparatuswhen the carriage is at either end of its travel. The carriage'ismounted on wheels 15 each rotatably mounted. on a stub-axle ll andresting on the lower flanges of channel members 52, which flanges thusform tracks for the wheels.

On each side of the carriage are vertical from one position to theother.

is also in communication with inlet 95' for by draulic fluid and anoutlet 96 for such fluid;

movable insleeve '98 mounted on the carriage H the'pin normallyprotruding from sleeve 98 and engaging with a recess in one of stops 99(one is shown) fixed togirder 52 at positions corresponding to each ofthe two positions of the cover'on the apparatus. Movement of the pin toengage or disengage it from the top is effected by means of lever I90.Towing handles l0! enable the carriage to be gripped to move it Thetemperature (Within the cover can be observed by recording thermometerE03 The use of the above apparatus will now be described as applied tothe production of sponge rubber mattresses from a foamed compoundedsleeves 18 one adjacent to each end, in which pillars 19 support thecover 15 by means of lugs 90 projecting laterally from the cover. Thelower ends of the two pillars on the same side of the carriage are eachconnected through a floating link 81 to one end of an arm 82 pivotednear its center .on shafts 82a passing through each side member 13 ofthe carriage, the other ends of the two arms on the same side of thecarriage being joined by, links 84. Links 84 are slidable along verticalrods 86 supported on the carriage H which rods in turn support hydrauliccylinders 85 and 85a.' (See Fig. VIII and Fig. X.)

cylinder 85 has an inlet 90 at the top and an inlet 9| at the bottom,the two being connected by pipes 92 and 93 to a 4-way valve 94 which Asshown in Fig. X

latexcompounded to gel in the cold. One mould is situated at eachvulcanizing station and can be closed by 'a-lid in two sections eachhaving inwardl projecting plugs, so that the mattress is moulded withrecesses on the one side.- It will be assumed that the carriage andcover are on the right hand side of the apparatus with the cover in araised position. The moulds rest on the top. of bars 55 to lie whollywithin the respective flat perimeter 5i of each station. The

mould at station 53 is then filled with foamed latex and the carriageand cover are then moved by means of towing handles I0! until the coveris directly over the vulcanizing station 55 and the lever I0!) is thenoperated to lock the carriage in position. The latex is allowed to gel,and Valve 94 is turned to put pipe 93 into 00111131111102: tion withoutlet 95 and pipe 92 into communication with inlet 95, thus supplyinghydraulic liquid to cylinder 85 above piston 87! and allowing liquid toescape from beneath it whereby the cover is lowered until the sealingstrip H is pressed against the perimeter 5|; the mould is thus in aclosed vulcanizing chamber formed by the cover 10 and trough 52. Thelatex is then allowed to gel, and steam is then admitted through inlets55, air being displaced through the trap attached to outlet 53;condensate will form and seal the trough against escape of steam. As thetemperature within the vulcanizing chamber reaches C. as indicated bythrmometer [93 the supply of steam is cut down so that the temperatureis maintained at substantially 100 C.'but no escape of steam through thetrap occurs.

When vulcanization is complete at station 53 the supply of steam is cutofi and cold water is admitted through the inlet 58 and is thus sprayedupon. the mould and then drains away through the outlet 53. This willcause condensation of steam left in the chamber and the sub-atmosphericpressure thus created will be relieved through the opening of the reliefvalves H92. While the moulds are cooling the empty mould at vulcanizingstation 54 is filled with foamed latex, and afterwards the supply ofcold water sion in the mould at the vulcanizing station 54 isjar'riedout as above. Meanwhile the lids of .the mould containing vulcanizedfoam in the chamber 53 are'removed, one section of the lid being placedin the draining space 56 at one end of the vulcanizing station and theother in the central draining space. The vulcanized mattress is removedfrom the mould, and mould and lid cleaned by water from a hose pipe, thelids in their respective drainin spaces and the mould while still onbars 59 over the trough 62 of the vulcanizing station. The cleaned mouldis then filled with foamed latex and the lids put in place. By this timevulcanization of the dispersion in the moulds in chamber 54 will havebeen completed and the cover is raised, brought back over chamber 53 andso on.

Having described my invention, I claim;

1. Apparatus for gelling and vulcanizing rubber articles comprisin abase for supporting rubber articles at two stations in side by siderelationship, a movable cover member, to form with the base at each saidstation a chamber for enclosing an article at said station, means fortransferring the said cover member from one station to the other, andmeans to admit steam 'within the cover at each of said stations.

2. Apparatus of claim 1 comprising at each :station a trough having aperiphery adapted to mate with the mouth of said cover, means for:supporting an article over said trough, and means for drainingcondensate collecting in said trough.

3. An apparatus according to claim 1 having means for preventing thedevelopment of a pressure substantially less than atmospheric pressurewithin said chamber.

4. An apparatus according to claim 1 wherein means for transferring thecover member comprises four parallel arms plvotally attached to eachcorner of the cover and to the frame of the apparatus.

5. An apparatus according to claim 1 in which themeans for transferringthe cover comprises a track disposed at each side of the base,a carriagemovable along said track, vertically movable supports for said covermounted on said carriage and hydraulic means mounted on said carriagefor raising and lowerin said supports and cover.

6. Apparatus of claim 1 having water spraying pipes in said cover memberand in said base at each said station and a supply system having abranch to said cover and a branch to each of said stations, a checkvalve betweensaid branch to said cover and each said branch to saidstations, and means for admitting water selectively to each of saidbranch pipes to said stations] THOMAS J AMES RIMBAULT DIBDIN.

REFERENCES CITED The following references are of record in the file of,this patent:

UNITED STATES PATENTS Number Name Date 201,943 Poland Apr. 2, 1878665,258 Nielsen et a1 Jan. 1, 1901 2,198,493 Freeman, Apr. 23, 19402,259,430 Soderquist Oct. 14, 1941 2,308,971 Carter Jan. 19, 19432,354,433 Carter July 25, 1944

1. APPARATUS FOR GELLING AND VULCANIZING RUBBER ARTICLES COMPRISING ABASE FOR SUPPORTING RUBBER ARTICLES AT TWO STATIONS IN SIDE BY SIDERELATIONSHIP, A MOVALBE COVER MEMBER, TO FORM WITH THE BASE AT EACH SAIDSTATION A CHAMBER FOR ENCLOSING AN ARTICLE AT SAID STATION, MEANS FORTRANSFERRING THE SAID COVER MEMBER FROM ONE STATION TO THE OTHER, ANDMEANS TO ADMIT STEAM WITHIN THE COVER AT EACH OF SAID STATIONS.